How do you recreate history? In a sense, Elk Roofing Products, an asphalt shingle manufacturer, does it every day with the help of its IndustrialSQL Server historian, provided by Wonderware, an Invensys company based in Lake Forest, Calif.
When Elk Roofing, a unit of Dallas-based ElkCorp., began operations in 1995 at a new, “green field” shingle factory in Shafter, Calif., the company selected Wonderware’s InTouch software to provide human-machine interface (HMI) visualization and industrial process control. But it wasn’t long before Elk realized that the internal historical database provided with InTouch was insufficient.
“We were only historizing about 200 tags at five-second intervals. It was a minimal amount of data, and it wasn’t answering the questions that we had,” says Paul Rogers, Elk Roofing systems engineer. “If something like a break in our line occurred, we had no way to go back, other than verbal accounts, and find out what happened in our process. So we were looking for a way to recreate history.”
With IndustrialSQL Server, installed about three years ago, Elk was able to achieve that goal. “We have 6,500 I/O (input/output) points and memory messages, and we’re able to basically take a snapshot of our entire process every two seconds and lay that down into IndustrialSQL,” Rogers relates. The data has proven invaluable, he says.
Among other things, Elk relies on IndustrialSQL Server for real-time event monitoring to head off production problems. “We’ve built in parameters on certain events, so if a pressure gets too high on a particular vessel, that can trigger an event, and we can react before it becomes an issue.”
When problems on the line do occur, such as a break in the asphalt and granule-coated fiberglass mat that moves through the company’s continuous process machines, Elk engineers can, in fact, “recreate history” to trace the sources of the problem, says Rogers. “Tension is a very important measurement point for us, so if a break happens, we can go back and see where those tensions spiked,” he notes. Elk personnel can then carry out proactive process control, such as changing speeds on particular rollers to relieve tension, or make other adjustments to ensure that the same problem doesn’t happen again.
Elk’s maintenance activities likewise benefit from the use of historical data stored on IndustrialSQL Server, Rogers says. Prior to a maintenance shutdown, for example, Elk engineers can check on which pieces of equipment on the packaging end of the line may have been recently prone to jams, he notes. This serves as a guide to those units that should receive maintenance attention during the shutdown.
The financial benefits that Elk gains from the use of IndustrialSQL Server are difficult to quantify, says Rogers. But he points out that downtime costs the company about $6,000 per hour. So just through downtime minimization alone—both through event monitoring and optimization of maintenance—the company’s savings have been substantial, he says.
“Without IndustrialSQL Server, we would be blind,” Rogers concludes.
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